Journal / Paper guides / A4 Paper Size in Inches: Dimensions & Conversion
Published 2026-02-25 · Updated 2026-05-01 · 4 min readSection / Journal
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A4 Paper Size in Inches: Dimensions & Conversion
A4 is 210×297 mm—about 8.27×11.69 in. See how it differs from US Letter, when to design in A4, and how to print without silent scaling.
PGPaperGens · writing about print·2026-02-25·Updated 2026-05-01·4 min read
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A4 is the global default “office page” in most countries outside the US/Canada. The ISO definition is 210 mm wide × 297 mm tall—roughly 8.27 in × 11.69 in (commonly rounded to two decimals in spec sheets).
It is not the same as US Letter (8.5 × 11 in). A4 is a few millimetres narrower and a few millimetres taller, so PDFs cross-imported without page box changes will reflow, clip, or auto-scale if the print dialog “helps.”
Millimetres, inches, and where rounding matters
- Exact width: 210 mm ≈ 8.2677 in
- Exact height: 297 mm ≈ 11.6929 in
For craft, bindery, or print shop work, work in millimetres; for US classroom conversations, use inches but expect ~0.02 in differences when you compare to physical rulers—manufacturing tolerances and print margins add more than that first.
A4 vs US Letter in one sentence
If you are in a US default software template, you are probably in Letter until you change the page size. If you are in a global template, you are probably in A4—export PDFs in the size you will print, not the size you “usually use.”
Read A4 vs Letter: which to choose for region-by-region decision rules.
Printing A4 PDFs without surprise scaling
- Set the document to A4 in the authoring app.
- Load A4 in the correct tray.
- Print at 100% / Actual size and disable “fit to page” for line-critical work.
When a printer has only Letter stock, do not treat scaling as harmless. Text-heavy pages may survive a small shrink, but measured templates do not. A 5 mm grid, handwriting band, or music staff becomes a different size when the driver squeezes A4 onto Letter.
A4 conversion table
| Unit | A4 width | A4 height |
|---|---|---|
| Millimetres | 210 mm | 297 mm |
| Centimetres | 21.0 cm | 29.7 cm |
| Inches | 8.2677 in | 11.6929 in |
| Rounded inches | 8.27 in | 11.69 in |
Use rounded inches for everyday explanation, but use millimetres or exact decimal inches when setting up templates, trim marks, or measured layouts.
Bookbinding and craft cut lines
A4’s taller, narrower page changes gutter loss when perfect-binding zines. Test fold signatures with scrap A4 before cutting US Letter patterns from online tutorials.
For craft templates, check both the outer page size and the inner safe area. A project that fits Letter width may feel tight on A4 because A4 is narrower. A worksheet that needs extra vertical room may benefit from A4 because the extra height gives space for instructions or answer lines.
Common A4 mistakes
- Exporting from a Letter document and assuming the PDF became A4 automatically.
- Printing A4 on Letter paper with Fit enabled, then wondering why grid spacing changed.
- Designing margins in inches while the rest of the workflow uses millimetres.
- Sending a single A4 file to a mixed US/international group without a Letter alternative.
- Trusting the preview thumbnail instead of checking PDF page properties.
The fix is simple but easy to skip: set the page size first, then design. Page-size conversion should be a layout step, not the final print-dialog rescue.
FAQ
Why does my ruler disagree with packaged “8.27 in”? Manufacturing tolerances and humidity swell paper—trust ISO millimetres for archival specs.
Can Chrome print true A4 on Letter hardware? Only if you load appropriately sized stock—drivers cannot magically resize physical sheets.
Should I design A4 templates in inches or millimetres? Use millimetres when the final page is A4. You can display inches for US readers, but millimetres match the standard and reduce rounding mistakes.
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